2014 Microchip Technology Inc. DS20005253A-page 1
MCP1642B/D
Features
• Up to 96% Typical Efficiency
• 1.8A Typical Peak Input Current Limit:
-I
OUT > 175 mA @ 1.2V VIN, 3.3V VOUT
-I
OUT > 600 mA @ 2.4V VIN, 3.3V VOUT
-I
OUT > 800 mA @ 3.3V VIN, 5.0V VOUT
-I
OUT > 1A @ VIN > 3.6V, 5.0V VOUT
• Low Start-Up Voltage: 0.65V, typical 3.3V VOUT
@ 1 mA
• Low Operating Input Voltage: 0.35V, typical 3.3V
VOUT @ 1 mA
• Output Voltage Range:
- Reference Voltage, VFB =1.21V
- 1.8V to 5.5V for the adjustable device option
- 1.8V, 3.0V, 3.3V and 5.0V for fixed VOUT
options
• Maximum Input Voltage VOUT <5.5V
• PWM Operation: 1 MHz
- Low Noise, Anti-Ringing Control
• Power Good Open-Drain Output
• Internal Synchrono us Rectifi er
• Intern al Com pen sation
• Inrush Current Limiting and Internal Soft-Start
• Selectable, Logic-Controlled Shutdown States:
- True Load Disconnect Option (MCP1642B)
- Input-to-Output Bypass Option (MCP1642D)
• Shutdown Current (All States): 1 µA
• Overtemperature Protection
• Available Packages:
- 8-Lead MSOP
- 8-Lead 2x3 DFN
Applications
• One, Two and Three-Cell Alkaline, Lithium
Ultimate and NiMH/NiCd Portable Products
• Single-Cell Li-Ion to 5V Converters
•PIC
® MCU Power
• USB Emergency Backup Charger from Batteries
• Personal Medical Products
• Wireless Sensors
• Hand-Held Instruments
• GPS Receivers
• +3.3V to +5.0V Distributed Power Supply
General Description
The MCP1642B/D devices are compact,
high-efficiency, fixed-frequency, synchronous step-up
DC-DC converters. This family of devices provides an
easy-to-use power supply solution for applications
powered by either one-cell, two-cell, or three-cell
alkaline, Ultimate Lithium, NiCd, NiMH, one-cell Li-Ion
or Li-Polymer batteries.
Low-vo lta ge tec hnolo gy al lows th e re gulato r to st art-u p
withou t hi gh i nrus h curre nt or output v ol t ag e ov ers ho ot
from a low voltage input. High efficiency is
accomplished by integrating the low-resistance
N-Channel Boost switch and synchronous P-Channel
switch. All compensation and protection circuitry are
integrated to minimize the number of external
components. An open-drain Power Good output is
provided to indicate when the output voltage is within
10% of regulation and facilitates the interface with an
MCU. Fo r st andb y app licati ons, MCP1 642B prov ide s a
“true output disconnect” from input to output while in
shutdown (EN = GND). An additional device option
(MCP164 2D) is a vaila ble an d con nect s “input to o utput
bypass” while in shutdown. Both options consume less
than 1 µA of input current.
For the adjustable (ADJ) device options, the output
voltage is s et b y a s ma ll ex tern al resi stor div ide r. Fixed
VOUT device options do not require external divider
resistors. Two package options, 8-lead MSOP and 8-
lead 2x3 DFN, are available.
Package Types
PG
NC
VOUT
SGND
PGND
1
2
3
4
8
7
6
5SW
VIN
EN
EP
9
PGND
SGND
PG
VFB
VOUT
SGND
PGND
1
2
3
4
8
7
6
5SW
VIN
EN
EP
9
6
1
2
3
8VIN
PGND
EN
VFB
PG
7SGND
5
4SW
VOUT
6
1
2
3
8VIN
EN
NC
PG
7
5
4SWVOUT
MCP1642B/D-xx
MSOP MCP1642B/D-xx
2x3 DFN*
MCP1642B/D-ADJ
MSOP MCP1642B/D-ADJ
2x3 DFN*
* Includes Expose d Thermal Pad (EP); see Table 3-1.
1.8A Input Current Switch, 1 MHz Low-Voltage Start-Up
Synchronous Boost Regulator
MCP1642B/D
DS20005253A-page 2 2014 Microchip Technology Inc.
Typical Application
VIN
GND
VFB
VOUT
5.0V
COUT
4.7...10 µF
CIN
4.7...10 µF
L
4.7 µH
SW
976 k
309 k
EN
VOUT
+
-
ALKALINE
1M
PG
ON
OFF
To PIC M CU I/O
+
-
ALKALINE
RTOP
RBOT RPG
VIN
GND
VOUT
3.3V
COUT
4.7...10 µF
CIN
4.7...10 µF
L1
4.7 µH
SW
EN
VOUT
+
-
ALKALINE
PG
ON
OFF
NC
0
10
20
30
40
50
60
70
80
90
100
1 10 100 1000
Efficiency (%)
I
OUT
(mA)
VIN = 2.5V, VOUT = 5.0V
VIN = 1.2V, VOUT = 3.3V
MCP1642B-33
MCP1642D-ADJ
From PIC® MCU I/O
VIN= 0.9 to 1.6V
VIN= 1.8 to 3.2V
2014 Microchip Technology Inc. DS20005253A-page 3
MCP1642B/D
1.0 ELECTRICAL
CHARACTERISTICS
Absolute Maximum Ratings †
EN, FB, VIN, VSW, VOUT – GND..........................+6.5V
EN, FB ......<maxim um of VOUT or VIN >(GND–0.3V)
Output Short-Circuit Curren t......................Con tin uou s
Output Curren t Byp ass Mo de....... ...... ..............800 mA
Power Dissipation ............................Internally Limited
Storage Temperature ..........................-65°C to +150°C
Ambient Temp. with Power Applied.......-40°C to +85°C
Operati ng Jun ct ion Te mp erat ure........ .-40°C to +125°C
ESD Protection On All Pins:
HBM........................................................4 kV
MM.........................................................300V
† Notice: S tresses above those listed under “Maximum
Ratings” may cause permanent damage to the device.
This is a stress rating only and functional operation of
the devi ce at those or any other c onditions ab ove those
indicated in the operational sections of this
specification is not intended. Exposure to maximum
rating conditions for extended periods may affect
device reliability.
DC CHARACTERISTICS
Electrical Characteris tics: Unless otherwise indicated, VIN = 1.2V, COUT =C
IN =10µF, L=4.7µH, V
OUT =3.3V,
IOUT =15mA, T
A= +25°C, MCP1642B/D-ADJ. Boldface specifications apply over the TA range of -40°C to +85°C.
Parameters Sym. Min. Typ. Max. Units Conditions
Input Characteristics
Minimum Start-Up Voltage VIN — 0.65 0.8 V Note 1
— 0.9 1.8 V MCP1642B/D-50, Note 1
Minimum Input Voltage
After Start-Up VIN —0.35 — V Note 1, Note 5
—0.5 — VNote 1, Note 5, MCP1642B/D-50
Output Voltage Adjust.
Range
(MCP1642B/D-ADJ)
VOUT 1.8 —5.5 VV
OUT VIN (MCP1642B/D-ADJ);
Note 2
Output Voltage
(MCP1642B/D-XX)VOUT —1.8 — VV
IN < 1.8V, MCP1642B/D-18,
Note 2
—3.0 — VV
IN < 3.0V, MCP1642B/D-30,
Note 2
—3.3 — VV
IN < 3.3V, MCP1642B/D-33,
Note 2
—5.0 — VV
IN < 5.0V, MCP1642B/D-50,
Note 2
Maximum Output Current IOUT —175 — mA1.2V V
IN, 1.8V VOUT, Note 5
—300 — mA1.5V V
IN, 3.3V VOUT, Note 5
—800 — mA3.3V V
IN, 5.0V VOUT, Note 5
Feedbac k Voltage VFB 1.173 1.21 1.247 V
Feedbac k Input
Bias Current IVFB —1.0 — nANote 5
Note 1: Resistive load, 1 mA.
2: For VIN >V
OUT, VOUT will not remain in regulation.
3: IQPWM is measured from VOUT; VOUT is externally supplied with a voltage higher than the nominal 3.3V
output (device is not switching), no load. VIN quiescent current will vary with boost ratio. VIN quiescent
current can be estimated by: (IQPWM *(V
OUT/VIN)).
4: 220 resistive load, 3.3V VOUT (15 mA).
5: Determined by characterization, not production tested.
MCP1642B/D
DS20005253A-page 4 2014 Microchip Technology Inc.
Quiescent Current –
PWM Mode IQPWM — 400 500 µA Measured at VOUT, EN = VIN,
IOUT =0mA, Note 3
Quiescent Current –
Shutdown IQSHDN —1 — µAV
OUT = EN = GND, IOUT = 0 mA
includes N-Channel and
P-Channel Switch Leakage
NMOS Switch Leakage INLK —0.5 — µAV
IN =V
SW =5V,
VOUT =5.5V,
VEN =V
FB =GND
PMOS Switch Leakage IPLK —0.2 — µAV
IN =V
SW = GND,
VOUT =5.5V
NMOS Switch
ON Resista nce RDS(ON)N —0.15 — VIN = 3.3V, ISW =250mA, Note 5
PMOS Switch
ON Resista nce RDS(ON)P —0.3 — VIN = 3.3V, ISW =250mA, Note 5
NMOS Peak
Switch Current Limit IN(MAX) —1.8 — ANote 5
Accuracy VFB% -3 — 3 % MCP1642B/D-ADJ, VIN =1.2V
VOUT% -3 — 3 % MCP1642B/D-18, VIN =1.2V
-3 — 3 % MCP1642B/D-30, VIN =1.2V
-3 — 3 % MCP1642B/D-33, VIN =1.2V
-3 — 3 % MCP1642B/D-50, VIN =2.5V
Line Regulation VFB/VFB)
/VIN|-0.5 0.01 0.5 %/V MCP1642B/D-ADJ,
VIN = 1 .5V to 3.0V, IOUT =25mA
VOUT/VOUT)
/VIN|-0.5 0.05 0.5 %/V MCP1642B/D-18,
VIN = 1 .0V to 1.5V, IOUT =25mA
-0.5 0.01 0.5 %/V MCP1642B/D-30,
VIN = 1 .5V to 2.5V, IOUT =25mA
-0.5 0.01 0.5 %/V MCP1642B/D-33,
VIN = 1 .5V to 3.0V, IOUT =25mA
-0.5 0.01 0.5 %/V MCP1642B/D-50,
VIN = 2 .5V to 4.2V, IOUT =25mA
Load Regulation VFB/VFB| -1.5 0.05 1.5 % IOUT =25mA to 150mA,
VIN =1.5V
VOUT/VOUT| -1.5 0.1 1.5 % MCP1642B/D-18, VIN =1.5V,
IOUT = 25 mA to 75 mA
-1.5 0.1 1.5 % MCP1642B/D-30, VIN =1.5V,
IOUT =25mA to 125mA
-1.5 0.1 1.5 % MCP1642B/D-33, VIN =1.5V,
IOUT =25mA to 150mA
— 0.5 — % MCP1642B/D-50, VIN =3.0V,
IOUT =25mA to 500mA, Note 5
DC CHARACTERISTICS (CONTINUE D)
Electrical Characteris tics: Unless otherwise indicated, VIN = 1.2V, COUT =C
IN =10µF, L=4.7µH, V
OUT =3.3V,
IOUT =15mA, T
A= +25°C, MCP1642B/D-ADJ. Boldface specifications apply over the TA range of -40°C to +85°C.
Parameters Sym. Min. Typ. Max. Units Conditions
Note 1: Resistive load, 1 mA.
2: For VIN >V
OUT, VOUT will not remain in regulation.
3: IQPWM is measured from VOUT; VOUT is externally supplied with a voltage higher than the nominal 3.3V
output (device is not switching), no load. VIN quiescent current will vary with boost ratio. VIN quiescent
current can be estimated by: (IQPWM *(V
OUT/VIN)).
4: 220 resistive load, 3.3V VOUT (15 mA).
5: Determined by characterization, not production tested.
2014 Microchip Technology Inc. DS20005253A-page 5
MCP1642B/D
Maximu m Duty Cycle DCMAX —90 — %Note 5
Switching Frequency fSW 0.85 1.0 1.15 MHz Note 5, IOUT = 65 mA,
for MCP1642B/D-50 VIN = 2.5V
EN Input Logic High VIH 75 ——% of V
IN IOUT =1mA,
for MCP1642B/D-50 VIN = 2.5V
EN Input Logic Low VIL —— 20 % of VIN IOUT =1mA,
for MCP1642B/D-50 VIN = 2.5V
EN Input Leakage Current IENLK —0.1 — µAV
EN =1.2V
Power Good Threshold PGTHF —90 — %V
FB Fallin g, Note 5
Power Good Hysteresis PGHYS —3 — %Note 5
Power Good Output Low PGLOW —0.4 — VI
SINK =5mA, V
FB =0V, Note 5
Power Good Output Del ay PGDELAY —600 — µsNote 5
Power Good Output
Response PGRES —250 — µsNote 5
Power Good Input Vo ltage
Operating Range VPG_VIN 0.9 — 5.5 V ISINK =5mA, V
FB =0V, Note 5
Power Good
Leakage Current PGLEAK —0.01 — µAV
PG =5.5V,
VOUT in Regulation, Note 5
Soft Start Time tSS — 550 — µs EN Low to High,
90% of VOUT, Note 4, Note 5
Thermal Shutdown
Die Temperature TSD —150 — CNote 5
Die Temperature
Hysteresis TSDHYS —35 — CNote 5
TEMPERATURE SPECIFICATIONS
Electrical Characteris tics: Unless otherwise indicated, VIN = 1.2V, COUT =C
IN =10µF, L=4.7µH, V
OUT =3.3V,
IOUT =15mA, T
A=+25°C.
Parameters Sym. Min. Typ. Max. Units Conditions
Temperature Ranges
Operati ng Amb ien t Temperature
Range TA-40 — +85 °C Steady State
Storage Temperature Range TA-65 — +150 °C
Maximum Junction Temper ature TJ— — +150 °C Transient
Package Thermal Resistances
Thermal Resistance, 8L-MSOP JA —211 —°C/W
Thermal Resistance, 8L-2x3 DFN JA —68 —°C/W
DC CHARACTERISTICS (CONTINUE D)
Electrical Characteris tics: Unless otherwise indicated, VIN = 1.2V, COUT =C
IN =10µF, L=4.7µH, V
OUT =3.3V,
IOUT =15mA, T
A= +25°C, MCP1642B/D-ADJ. Boldface specifications apply over the TA range of -40°C to +85°C.
Parameters Sym. Min. Typ. Max. Units Conditions
Note 1: Resistive load, 1 mA.
2: For VIN >V
OUT, VOUT will not remain in regulation.
3: IQPWM is measured from VOUT; VOUT is externally supplied with a voltage higher than the nominal 3.3V
output (device is not switching), no load. VIN quiescent current will vary with boost ratio. VIN quiescent
current can be estimated by: (IQPWM *(V
OUT/VIN)).
4: 220 resistive load, 3.3V VOUT (15 mA).
5: Determined by characterization, not production tested.
MCP1642B/D
DS20005253A-page 6 2014 Microchip Technology Inc.
NOTES:
2014 Microchip Technology Inc. DS20005253A-page 7
MCP1642B/D
2.0 TYPICAL PERFORMANCE CURVES
Note: Unless otherwise indicated, VIN =EN=1.2V, C
OUT =C
IN =10µF, L=4.7µH, V
OUT =3.3V, I
LOAD =15mA,
TA= +25°C (MCP1642B/D-ADJ, MSOP-8 package).
FIGURE 2-1: VOUT IQPWM vs. Ambient
Temperature.
FIGURE 2-2: 3.3V VOUT vs. Ambient
Temperature.
FIGURE 2-3: 5.0V VOUT vs. Ambient
Temperature.
FIGURE 2-4: 2.0V VOUT Mode Efficiency
vs. IOUT.
FIGURE 2-5: 3.3V VOUT Mode Efficiency
vs. IOUT.
FIGURE 2-6: 5.0V VOUT Mode Efficiency
vs. IOUT.
Note: The gra phs and table s pro vi ded follo w ing this note ar e a st a tis tic al sum ma ry ba sed on a limi ted nu mb er of
samples and are provided for informational purposes only. The performance characteristics listed herein
are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified
operating range (e.g., outside specified power supply range) and therefore outside the warranted range.
300
325
350
375
400
425
450
475
500
-40 -25 -10 5 20 35 50 65 80
I
Q
PWM Mode (µA)
Ambient Temperature (°C)
VOUT = 3.3V
VOUT = 5.0V
VIN = 1.2V
VOUT = 2.0V
3.304
3.306
3.308
3.310
3.312
3.314
-40 -25 -10 5 20 35 50 65 80
V
OUT
(V)
Ambient Temperature (°C)
IOUT = 50 mA VIN = 1.8V
VIN = 1.2V
4.980
4.985
4.990
4.995
5.000
5.005
5.010
-40 -25 -10 5 20 35 50 65 80
V
OUT
(V)
Ambient Temperature (°C)
VIN = 2.5V
IOUT = 50 mA
VIN = 1.8V
0
10
20
30
40
50
60
70
80
90
100
0.1 1 10 100 1000
Efficiency (%)
IOUT (mA)
VOUT = 2.0V
VIN = 1.2V
VIN = 1.6V
0
10
20
30
40
50
60
70
80
90
100
0.1 1 10 100 1000
Efficiency (%)
IOUT (mA)
VOUT = 3.3V
VIN = 1.2V
VIN = 2.5V
0
10
20
30
40
50
60
70
80
90
100
0.1 1 10 100 1000
Efficiency (%)
IOUT (mA)
VOUT = 5.0V
VIN = 2.5V
VIN = 3.6V
MCP1642B/D
DS20005253A-page 8 2014 Microchip Technology Inc.
Note: Unless otherwise indicated, VIN =EN=1.2V, C
OUT =C
IN =10µF, L=4.7µH, V
OUT =3.3V, I
LOAD =15mA,
TA= +25°C (MCP1642B/D-ADJ, MSOP-8 package).
FIGURE 2-7: Maximum IOUT vs. VIN.
FIGURE 2-8: 3.3V VOUT vs. VIN.
FIGURE 2-9: 3.3V VOUT Minimum
Start-Up and Shutdown VIN into Resistive Load
vs. IOUT.
FIGURE 2-10: 5.0V VOUT Minimum
Start-Up and Shutdown VIN into Resistive Load
vs. IOUT.
FIGURE 2-11: fSW vs . Ambi ent
Temperature.
FIGURE 2-12: PWM Puls e-Sk ip ping Mode
Threshold vs. IOUT.
0
200
400
600
800
1000
1200
0.8 1.2 1.6 2 2.4 2.8 3.2 3.6 4
I
OUT
(mA)
VIN (V)
VOUT = 3.3V
VOUT = 2.0V
VOUT = 5.0V
TA = +25°C
TA = +85°C
3.290
3.292
3.294
3.296
3.298
3.300
3.302
3.304
0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3
V
OUT
(V)
VIN (V)
TA=-40°C
IOUT = 15 mA
TA=25°C
TA=85°C
0.30
0.35
0.40
0.45
0.50
0.55
0.60
0.65
0.70
0 20406080100
V
IN
(V)
I
OUT
(mA)
Start-up
Shutdown
VOUT = 3.3V
0.30
0.50
0.70
0.90
1.10
1.30
1.50
0 20406080100
V
IN
(V)
IOUT (mA)
Start-up
Shutdown
VOUT = 5.0V
988
992
996
1000
1004
-40 -25 -10 5 20 35 50 65 80
Switching Frequency (kHz)
Ambient Temperature (°C)
VOUT = 3.3V
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
0 5 10 15 20 25
V
IN
(V)
IOUT (mA)
VOUT = 3.3V
VOUT = 5.0V
VOUT = 2.0V
2014 Microchip Technology Inc. DS20005253A-page 9
MCP1642B/D
Note: Unless otherwise indicated, VIN =EN=1.2V, C
OUT =C
IN =10µF, L=4.7µH, V
OUT =3.3V, I
LOAD =15mA,
TA= +25°C (MCP1642B/D-ADJ, MSOP-8 package).
FIGURE 2-13: Average of No Load Input
Current vs. VIN.
FIGURE 2-14: N-Channel and P-Channel
RDSON vs. > of VIN or VOUT.
FIGURE 2-15: MCP1642B/D 3.3V VOUT
Light Load PWM Mod e Wavefor ms.
FIGURE 2-16: MCP1642B/D High Load
PWM Mode Wavefor ms.
FIGURE 2-17: 3.3V Start-Up After Enable.
FIGURE 2-18: 3.3V Start-Up When
VIN =V
ENABLE.
0.1
1
10
100
0.8 1.2 1.6 2 2.4 2.8 3.2 3.6 4 4.4
I
IN
(mA)
VIN (V)
VOUT = 2.0V
VOUT = 3.3V
VOUT = 5.0V
0
0.05
0.1
0.15
0.2
0.25
0
0.5
1
1.5
2
2.5
1 1.4 1.8 2.2 2.6 3 3.4 3.8 4.2
Switch Resistance (
:
)
> VIN or VOUT
P - Channel
N - Channel
IOUT =1mA
1µs/div
VOUT
20 mV/div
AC coupled
IL
VSW
1V/div
100 mA/div
IOUT =100mA
VSW
IL
1µs/div
VOUT
20 mV/div
AC coupled
2V/div
200 mA/div
IOUT =15mA
VOUT
1V/div
VEN
1V/div
200 µs/div
VIN
1V/div
IL
200 mA/div
2V/div
VOUT
200 µs/div
1V/div
VIN
I = 15 mA
OUT
MCP1642B/D
DS20005253A-page 10 2014 Microchip Technology Inc.
Note: Unless otherwise indicated, VIN =EN=1.2V, C
OUT =C
IN =10µF, L=4.7µH, V
OUT =3.3V, I
LOAD =15mA,
TA= +25°C (MCP1642B/D-ADJ, MSOP-8 package).
FIGURE 2-19: MCP1642B 3.3V VOUT Load
Transient Waveforms.
FIGURE 2-20: 3.3V VOUT Line Transient
Waveforms.
I
OUT
100 mA/div
Step from 20 mA to 150 mA
400 µs/div
V
OUT
100 mV/div
AC coupl e d
VIN
1V/div
Step from 1.2V to 2.4V
400 µs/div
V
OUT
100 mV/div
AC coupled
2014 Microchip Technology Inc. DS20005253A-page 11
MCP1642B/D
3.0 PIN DESCRIPTIONS
The descriptions of the pins are listed in Table 3-1.
3.1 Enabl e Pin (EN)
The EN pin is a logic-level input used to enable or
disable device switching and lower quiescent current
while disabled. A logic high (>75% of VIN) will enable
the regulator output. A logic low (<20% of VIN) will
ens ure that the re gulator is disabled.
3.2 Feedback Voltage Pin (V FB)
The VFB pin is used to provide output voltage regulation
by using a resistor divider for the ADJ device option.
The typical feedback voltage will be 1.21V, with the
output vo ltage in regulat ion.
3.3 Power Good Pin (PG)
The Power Good pin is an open-drain output which can
be tied to VOUT using a pull-up resistor. It turns low
when VOUT drops below 10% of its nominal value.
3.4 Output Voltage Pin (VOUT)
The output voltage pin connects the integrated
P-Channel MOSFET to the output capacitor. The FB
voltage divider is also connected to the VOUT pin for
voltage regulation for the “ADJ” option.
3.5 Switch Node Pin (SW)
Connect the inductor from the input voltage to the SW
pin. The SW pin carries inductor current and can be as
high as 1.8A peak. The integrated N-Channel switch
drain and integrated P-Channel switch source are
internally connected at the SW node.
3.6 Power Ground Pin (PGND)
The power ground pin is used as a return for the
high-current N-Channel switch. The PGND and SGND
pins are connected externally.
3.7 Signal Ground Pin (SGND)
The signal ground pin is used as a return for the
integrated VREF and error amplifier. The SGND and
power ground (PGND) pins are connected externally.
3.8 Power Suppl y Input Voltage Pin
(VIN)
Connect the input voltage source to VIN. The input
source should be decoupled to GND with a 4.7 µF
minimum cap ac i to r.
3.9 Exposed Thermal Pad (EP)
There is no internal electrical connection between the
Exposed Thermal Pad (EP) and the SGND and PGND
pins. They must be connected to the same electric
potential on the Printed Circuit Board (PCB).
TABLE 3-1: PIN FUNCTION TABLE
MCP1642B/D-XX
MSOP, 2x3 DFN MCP1642B/D-ADJ
MSOP, 2x3 DFN Symbol Description
1 1 EN Enable pin. Logic high enables operation. Do not allow this pin
to float.
2 — NC Not Connected.
—2V
FB Reference Voltage pin. Connect VFB to an external resistor
divide r to se t the outpu t volt age (fo r fix ed VOUT options, th is pin
is not connected).
3 3 PG Ope n-Drain Power Good pin. Indic ates when the output v oltage
is within regulation.
44V
OUT Boost Converter Output.
5 5 SW Boost and Rectifier Switch input. Connect boost inductor
between SW and VIN.
66P
GND Power Ground reference.
77S
GND Signal Ground reference.
88V
IN Input supply voltage. Local bypass capacitor required.
9 9 EP Exposed Thermal Pad (2x3 DFN only).
MCP1642B/D
DS20005253A-page 12 2014 Microchip Technology Inc.
NOTES:
2014 Microchip Technology Inc. DS20005253A-page 13
MCP1642B/D
4.0 DETAILED DESCRIPTION
4.1 Devi ce Option Overview
The MCP1642B/D family of devices is capable of low
start -up voltage and delive rs high efficie ncy over a wide
load range for single-cell, two-cell, three-cell alkaline,
Ultimate Lithium, NiMH, NiCd and single-cell Li-Ion
battery inputs. A high level of integration lowers total
system co st, e as es i mp lem en t ation a nd re duc es boa rd
area.
The devices feature low start-up voltage, fixed and
adjustable output voltage, PWM mode operation,
integr ate d sy nc hro nou s s w itch, internal c om pen sa tio n,
low noise anti-ringing control, inrush current limit and
soft s tart.
There are two shutdown options for the MCP1642B/D
family:
• True Output Disconnect mode (MCP1642B)
• Input-to-Output Bypass mode (MCP1642D)
4.1.1 TRUE OUTPUT DISCONNECT
MODE OPTION
The MCP1642B device incorporates a true output
disconnect feature. With the EN pin pulled low, the
output of the MCP1642B is isolated or disconnected
from the input by turning off the integrated P-Channel
switch and removi ng the switc h bulk diode conn ec tio n.
This removes the DC path that is typical in boost
convert ers, whi ch al lows th e outp ut to b e dis connecte d
from the input. During this mode, less than 1 µA of
current is consumed from the input (battery). True
output disconnect does not discharge the output.
4.1.2 INPUT-TO-OUTPUT BYPASS MODE
OPTION
The MCP1642D device incorporates the
Input-to-Output Bypass shutdown option. With the EN
input pulled low, the output is connected to the input
using the internal P-Channel MOSFET. In this mode,
the current drawn from the input (battery) is less than
1 µA with no load . The Input-to-O utput Byp ass mode is
used when the input volt age is high enoug h for the load
to operate (e.g. PIC MCU operating in sleep mode).
When a higher regulated output voltage and load
current are necessary, the EN pin must be pulled high,
enabling the boost converter.
4.1.3 ADJU STABLE OUTPUT VOLTAGE
OPTION
For the MCP1642B/D ADJ option, the output voltage is
adjustable with a resistor divider over a 1.8V minimum
to 5.5V maximum range. The middle point of the
resistor divider connects to the VFB pin. High-value
resistors are recommended to minimize quiescent
current to keep efficiency high at light loads. The
reference v oltage is VFB = 1.21V.
4.1.4 FIXED OUTPUT VOLT AGE OPTION
For the fixed output volt age optio n of the MCP1642B/D
devices, the VFB pin is not connected. There is an
internal feedback divider which minimizes quiescent
current to keep efficiency high at light loads.
The value of the internal divider is 815 k typical.
The fixed set values are: 1.8V, 3.0V, 3.3V and 5.0V.
TABLE 4-1: PART NUMBER SELECTION
BY SHUTDOWN OPTION
Part Number True Output
Disconnect Input-to-Output
Bypass
MCP1642B-ADJ
(or -18; 30; 33; 50) X—
MCP1642D-ADJ
(or -18; 30; 33; 50) —X
MCP1642B/D
DS20005253A-page 14 2014 Microchip Technology Inc.
4.2 Funct ional Description
The MCP1642B/D devices are compact,
high-efficiency, fixed-frequency, step-up DC-DC
converters that provide an easy-to-use power supply
solution for applications powered by either one-cell,
two-cell, or three-cell alkaline, Ultimate Lithium, NiCd,
or NiMH, or one-cell Li-Ion or Li-Polymer batteries.
Figure 4-1 depicts the functional block diagram of the
MCP1642B/D dev ic es .
FIGURE 4-1: MCP1642B/D Block Diagram.
EN
PGND
0V
Soft-Start
Oscillator S
1.21V
SW
EA
VFB
0.9 x VREF
PG
*
SGND
VOUT
VIN Internal
Bias
Gate Drive
and
Shutdown
Control
Logic
Direction
Control
IZERO
ILIMIT
ISENSE
Slope
Compensation
PWM
Logic
VOUT
VFB (NC)
* Available in Fixed Output option only. See
Section 4.2.4 “Fixed Output Voltage”.
OCREF
2014 Microchip Technology Inc. DS20005253A-page 15
MCP1642B/D
4.2.1 LOW-VOLTAGE START-UP
The MCP164 2B/D d evices a re capable of sta rting fro m
a low input voltage. Start-up voltage is typically 0.65V
for a 3.3V output and 1 mA resistive load.
When enabled, the internal start-up logic turns the
rectifying P-Channel switch on until the output
capacitor is charged to a value close to the input
voltage. During this period, the rectifying switch is
current-limited at approximately 125 mA, which limits
the start-up under heavy resistive load condition. After
charging the output capacitor to the input voltage, the
device starts switching. A ring oscillator is only used
until the main RC oscillator has enough bias and is
ready. The device runs open-loop until the output rises
enough to start the RC oscillator. During this time, the
boost switch current is limited to 50% of its nominal
value. Once the output voltage reaches a high value,
normal closed-l oop PW M operation is initiated.
Then, during the end sequence of the start-up, the
MCP1642B/D devices charge an internal capacitor with
a very weak current source. The voltage on this
capacitor, in turn, slowly ramps the current limit of the
boost switch to its nominal value (1.8A typical). The
soft-start capacitor is completely discharged in the
event of a commanded shutdown or a thermal
shutdown.
There is no undervoltage lockout feature for the
MCP1642B/D devices. The devices will start up at the
lowest possible voltage and run down to the lowest
possible voltage. For typical battery applications,
deeply discharged batteries may result in
"motor-boating" (emission of a low-frequency tone).
4.2.2 PWM MO DE OP ER AT IO N
In normal PWM operation, the MCP1642B/D devices
operate as fixed-frequency, synchronous boost
converters. The switching frequency is internally
maintained with a precision oscillator typically set to
1 M Hz. At light loads, the MCP1642B/D devices begin
to skip pulses . Figure 2-12 repres ents the input voltag e
versus load current for the pulse-skipping threshold in
PWM mode. By operating in PWM-only mode, the out-
put ripple remains low and the frequency is constant.
Operating in fixed PWM mode results in low efficiency
during lig ht load operation but has low output ripple and
noise for the supplied load.
Lossless current sensing converts the peak current
signal to a voltage to sum with the internal slope
compen sa tion. Thi s su mm ed s ign al is com p a red to th e
voltage error amplifier output to provide a peak current
control command for the PWM signal. The slope
compensation is adaptive to the input and output
voltage. Therefore, the converter provides the proper
amount of slope compensation to ensure stability, but is
not excessive, which causes a loss of phase margin.
The peak current limit is set to 1.8A typical.
4.2.3 ADJUSTABLE OUTPUT VOLTAGE
The MCP1642B/D-ADJ output voltage is adjustable
with a resistor divider over a 1.8V minimum to 5.5V
maximum range. High-value resistors are
recommended to minimize quiescent current to keep
efficiency high at light loads.
4.2.4 FIXED OUTPUT VOLTAGE
MCP1642B/D-XX has the feedback divider included.
Four output values are available: 1.8V, 3.0V, 3.3V and
5.0V. For this option, pin 2 remains unconnected.
The value of the internal divider is 815 k typical.
4.2.5 MAXIMUM OUTPUT VOLTAGE
The maximum output current of the devices is
dependent upon the input and output voltage. For
example, to ensure a 200 mA load current for
VOUT = 3.3V, a typical value of 1.3V input voltage is
necessary. If an application is powered by one Li-Ion
battery (VIN from 3.0 V to 4.2V), the ty pical loa d c urre nt
the MCP1642B/D devices can deliver is close to
800 mA at 5.0V output (see Figure 2-7).
4.2.6 ENABLE PIN
The enable pin is used to turn the boost converter on
and off. The enable threshold voltage varies with input
voltage. To enable the boost converter, the EN voltage
level must be greater than 75% of the VIN voltage. To
disable the boost converter, the EN voltage must be
less than 20% of the VIN voltage.
4.2.7 POWER GOOD OUTPUT PIN
The MCP1642B/D devices have an internal
comparator which is triggered when VOUT reaches 90%
of regulation. An open-drain transistor allows
interfacing with an MCU. It can sink up to a few mA
from the power line at which the pull-up resistor is
connected. See the DC Characteristics table for
details.
4.2.8 INTERNAL BIAS
The MCP1642B/D devices get their start-up bias from
VIN. Once the output exceeds the input, bias comes
from the output. Therefore, once started, operation is
completely independent of VIN. Operation is only
limited by the output power level and the input source
series r esistance. When started, the output will remain
in regulation down to 0.35V typical with 1 mA output
current for low source impedance inputs.
MCP1642B/D
DS20005253A-page 16 2014 Microchip Technology Inc.
4.2.9 INTERNAL COMPENSATION
The error amplifier, with its associated compensation
network, completes the closed-loop system by
comparing the output voltage to a reference at the
input of the error amplifier, and feeding the amplified
and inverted signal to the control input of the inner
current loop. The compensation network provides
phase leads and lags at appropriate frequencies to
cancel excessive phase lags and leads of the power
circuit. All necessary compensation components and
slope compensation are integrated.
4.2.10 SHORT-CIRCUIT PROTECTION
Unlike most boost converters, the MCP1642B/D
devices allow their output to be shorted during normal
operation. The internal current limit and
overtemperature protection limit excessive stress and
protect the device during periods of short circuit,
overcurrent and overtemperature. While operating in
the Input-to-Output Bypass mode, the P-Channel
current limit is inhibited to minimize quiescent current.
4.2. 11 LOW NOISE OPERATION
The MCP1642B/D devices integrate a low-noise
anti-ring switch that damps the oscillations typically
observe d at the switc h node o f a boost conve rter whe n
operating in the Discontinuous Inductor Current mode.
This removes the high-frequency radiated noise.
4.2.12 OVERTEMPERATURE
PROTECTION
Overtemperature protection circuitry is integrated into
the MCP1642B/D devices. This circuitry monitors the
device junction temperature and shuts the device off if
the junction temperature exceeds the typical +150°C
threshold. If this threshold is exceeded, the device will
automatically restart when the junction temperature
drops by 35°C. The soft start is reset during an
overtemperature condition.
2014 Microchip Technology Inc. DS20005253A-page 17
MCP1642B/D
5.0 APPLICATION INFORMATION
5.1 Typical Applications
The MC P1 642 B/D s ynch ronous b oos t r egu lat ors oper-
ate over a wide input and output voltage range. The
power efficiency is high for several decades of load
range. Output current capability increases with the
input volta ge a nd decrea ses w ith the inc rea sing outp ut
voltage. The maximum output current is based on the
N-Channel peak current limit. Typical characterization
curves in this data sheet are presented to display the
typical output current capability.
5.2 Adjustable Output Voltage
Calculations
To calculate the resistor divider values for the
MCP1642B/D, the following equation can be used.
Where RTOP is connected to VOUT, RBOT is connected
to GND and both are connected to the VFB input pin:
EQUATION 5-1:
There are some potential issues with higher-value
resistors. For small surface-mount resistors,
environment contamination can create leakage paths
that significantly change the resistive divider ratio,
which in turn affects the output voltage. The FB input
leakage current can also impa ct the divider and change
the output voltage tolerance.
For boost converters, the removal of the feedback
resistors during operation must be avoided. In this
case, the output voltage will increase above the abso-
lute maximum output limits of the MCP1642B/D and
damage the device (for additional information, see
Application Note AN1337).
Overshoots and undershoots on pulsed load
applications are reduced by adding a zero in the
compensation loop. A small capacitance (for example,
27 or 33 pF) in p ara lle l w i th an upp er fe edback res ist or
will reduce ou tput spi kes. Thi s small c apacitance also
atten uates t he low-fre quenc y com ponent on the o utput
ripple that might appear w hen the dev ic e su ppl ies lig ht
loads (ranging from 75 to 150 mA) and on condition
that (VOUT –V
IN) < 0.6V (see the application example
in Figure 6-1).
5.2.1 VIN >V
OUT SITUATION
For VIN >V
OUT, the output voltage will not remain in
regulation. VIN >V
OUT is an unusual situation for a
boost converter, and there is a common issue when
two alkali ne cells (2 x 1.6V typical) are used to boost to
3.0V output. A minimum headroom of approximately
200 to 300 mV between VOUT and VIN must be
ensured, unless a low frequency higher than the PWM
output ripple on VOUT is expected. This ripple and its
frequency are VIN dependent.
5.3 Power Good Output
The Power Good output is meant to provide a method
that gives information about the output state of the
device . The Po wer Good comp ara tor i s trigg ered whe n
VOUT reaches ap pro ximately 90% of regu lat ion (on the
falling edge).
The PG pin is an open-drain output, which should be
connec ted to VOUT through a n external pu ll-up resi stor.
It is recommended to use a high-value resistor (to sink
µA from output) in order to use less power while
interfacing with an I/O PIC MCU port.
The Power Good block is internally supplied by the
maximum between the input and output voltage, and
the minimum voltage necessary is 0.9V. This is
import an t for appl ic ati ons in whic h t he Pow er G ood pi n
is pulled-up to an external supply. If the output voltage
is less than 0.9V (e.g., due to an overcurrent situation
or an output short circuit, and also if the device is in
Shutdown - EN = GND), the input voltage has to be
high enough to drive the Power Good circuitry.
Power Good delay time is measured between the time
when VOUT starts to regulate and the time when there
is a response from Power Good output. Power Good
response time is measured between the time when
VOUT goes out of regulation with a 10% drop, and the
time w hen Power G ood o utput ge ts t o a low le vel. Bo th
Power Good delay time and Power Good response
time are specified in the DC Characteristics table.
Addition ally, there are no b lanking t ime or delays ; there
is only a 3% hysteresis of th e Power Good comp arato r .
Due to the dynamic response, MCU must interpret
longer transients.
EXAMPL E 1:
VOUT =3.3V
VFB = 1.21V
RBOT =309k
RTOP =533.7k (standard value = 536 k)
EXAMPL E 2:
VOUT =5.0V
VFB = 1.21V
RBOT =309k
RTOP =967.9k (standard value = 976 k)
RTOP RBOT VOUT
VFB
-------------1–


=
MCP1642B/D
DS20005253A-page 18 2014 Microchip Technology Inc.
When VOUT resumes to a v alue hi gher th an 93%, the
PG pin swi tches to hi gh level.
FIGURE 5-1:
Power Good T iming Diagram
.
5.4 Input Capacitor Selecti on
The boost input current is smoothed by the boost
inductor, reducing the amount of filtering necessary at
the input. Some capacitance is recommended to
provide decoupling from the source. Low ESR X5R or
X7R are well suited, since they have a low temperature
coefficient and small size. For light-load applications,
4.7 µF of capacitance is sufficient at the input. For
high-power applications that have high source
impedance or long leads which connect the battery to
the input, 10 µF of capacitance is recommended.
Addition al input cap acit anc e can be added to provide a
stab le input volt ag e.
Table 5-1 contains the recommended range for the
input capacitor value.
5.5 Output Capac it or Selection
The output capacitor helps provide a stable output
voltage during sudden load transients and reduces the
outp ut vol tage r ippl e. As w ith t he in put c apacito r, X 5R
and X7R ceramic capacitors are well suited for this
application. Using other capacitor types (aluminum or
tant alum) w ith large ESR ha s impac t on the conv erter's
efficiency (see AN1337) and maximum output power.
The MCP1642B/D devi ces are internally compensated,
so output capacitance range is limited. See Table 5-1
for the recommended output capacitor range.
An output c apacitance hig he r than 10 µF adds a bet ter
load step response and high-frequency noise
attenuat ion, e specially while ste pping from light c urrent
loads to heavy current loads. In addition, 2 x 10 µF
output capacitors ensure a better recovery of the output
after a short period of overloading.
While the N-Channel switch is on, the output current is
supplied by the output capacitor COUT. The amount of
output capacitance and equivalent series resistance
will have a significant effect on the output ripple
voltage. While COUT provides load current, a voltage
drop also appears across its internal ESR that results
in ripple voltage.
EQUATION 5-2:
Table 5-1 contains the recommended range for the
input and output capacitor value.
5.6 Inductor Selection
The MCP1642B/D devices are designed to be used
with small surface-mount inductors; the inductance
value can range from 2.2 µH to 6.8 µH. An inductance
value of 4.7 µH is recommended to achieve a good
balance between the inductor size, the converter load
transient response and the minimized noise.
Several parameters are used to select the correct
inductor: maximum rated current, saturation current
and copper resist ance (ESR). For boost con verters, the
inductor current can be much higher than the output
current. The lower the inductor ESR, the higher the
efficiency of the converter: a common trade-off in size
versus efficiency.
The saturation current typically specifies a point at
which the ind uct ance ha s rolled off a percentage of the
rated value. This can range from a 20% to 40%
reduction in inductance. As inductance rolls off, the
inductor ripple current increases, as does the peak
switch current. It is important to keep the inductance
from rolling off too much, causing switch current to
reach the peak limit.
PG
RESPONSE
PG DELAY
VOUT
PG
600 µs (typ.) 250 µs (typ.)
TABLE 5-1: CAPACITOR VALUE RANGE
CIN COUT
Minimum 4.7 µF 10 µF
Maximum — 100 µF
TABLE 5-2: MCP1642B/D
RECOMMENDED INDUCTORS
Part Number Value
(µH) DCR
(typ.) ISAT
(A) Size
WxLxH (mm)
Coilcraft
LPS4018-472 4.7 0.125 1.9 4.1x4.1x1.8
XFL4020-472 4.7 0.057 2.7 4.2x4.2x2.1
LPS5030-472 4.7 0.083 2 5x5x3
LPS6225-472 4.7 0.065 3.2 6.2x6.2x2.5
MSS6132-472 4.7 0.043 2.84 6.1x6.1x3.2
Würth Elektronik
744025004 Type WE-TPC 4.7 0.1 1.7 2.8x2.8x2.8
744042004 WE-TPC 4.7 0.07 1.65 4.8x4.8x1.8
744052005 WE-TPC 5 0.047 1.8 5.8x5.8x1.8
7447785004 WE-PD 4.7 0.06 2.5 6.2x5.9x3.3
TDK/EPCOS
B82462A2472M000 4.7 0.084 2.00 6.0x6.0x2.5
B82462G4472M 4.7 0.04 1.8 6.3x6.3x3.0
IOUT COUT dV
dt
-------


=
Where:
dV = Ripple voltage
dt = ON time of the N-Channel switch
(DC x 1/FSW)
2014 Microchip Technology Inc. DS20005253A-page 19
MCP1642B/D
5.7 Thermal Calculations
The MCP16 42B/D devices are available in two differe nt
packages (MSOP-8 and 2 x 3 DFN-8). By calculating
the power dissipation and applying the package
thermal resistance (JA), the junction temperature is
estimated. The maximum continuous junction
temperature rating for the MCP1642B/D family of
devices is +125°C.
To quickly estimate the internal power dissipation for
the switching boost regulator, an empirical calculation
using measured efficiency can be used. Given the
measured efficiency, the internal power dissipation is
estimated by Equation 5-3.
EQUATION 5-3:
The difference betwee n the firs t term , i npu t p ower, and
the seco nd term, power de livered, is th e power dissip a-
tion of the MCP1642B/D devices. This is an estimate
assuming that most of the power lost is internal to the
MCP1642B/D and not CIN, COUT and the inductor.
There is some percentage of power lost in the boost
inductor, with very little loss in the input and output
capac itors. F or a mor e accur ate est imation of in ternal
power dissipation, subtract the IINRMS2xL
ESR power
dissipation.
5.8 PCB Layout Information
Good printed circuit board layout techniques are
important to any switching circuitry, and switching
power supplies are no different. When wiring the
switching high-current paths, short and wide traces
should b e used. Th erefore, it is import ant th at the inp ut
and outp ut capaci tors be place d as close as p ossible to
the MCP1642B/D to minimize the loop area.
The feedback resistors and feedback signal should be
routed aw ay from the switchi ng node and the s witching
current l oop. W hen po ssib le, gro und pl anes and tra ces
should be used to help shield the feedback signal and
minimize noise and magnetic interference.
FIGURE 5-2: MCP1642B/D Recommended Layout, Applicable to Both Packages.
VOUT IOUT
Efficiency
--------------------------------


VOUT IOUT
–PDis
=
COUT
L
CIN
+VIN
+VOUT
MCP1642
Enable
RBOT
GND
Via To Bottom
Plane
1
RTOP
Power Good
MCP1642B/D
DS20005253A-page 20 2014 Microchip Technology Inc.
6.0 TYPICAL APPLICATION CIRCUITS
FIGURE 6-1: Portable USB Powered by Li-Ion.
FIGURE 6-2: Portable USB Powered by Two Energizer® MAX® AA or Energizer® Ultimate Lithium
AA Batteries with the 5.0V Fixed Option of the MCP1642B.
VIN
PGND
VFB
SW
VIN
3.3V to 4.2V
VOUT
5.0V @ min. 500 mA
COUT
10 µF
CIN
10 µF
L
4.7 µH
VOUT
+
-
976 k
309 k
SGND
LI-ION
EN
PG
CC
27 pF
RBOT
RTOP
MCP1642B-ADJ
VIN
PGND
PG
SW
VIN
1.8V to 3.6V
VOUT
5.0V @ min. 500 mA
COUT
10 µF
CIN
10 µF
L
4.7 µH
VOUT
+
-SGND
EN
+
-
NC
12.7
1.8 0.3
28.7
5.8
2.3
0.0
5.0
10.0
15.0
20.0
25.0
30.0
50 mA 250 mA 500 mA
Service Estimate (hours)
Constant Output Current with 5V DC V
OUT
Energizer® MAX® AA
Energizer® Ultimate Lithium AA
Energizer
®
Ultimate Lithium AA
Energizer®MAX®AA
Note: Service estimates apply to using two Energizer® MAX® AA or Energizer® Ultimate Lithium AA
batteries as the power source. Note that, if PG or feedback divider network is used, some
addition al input drain current should b e include d, but t here will b e negligib le effec ts on the servic e
estimates at these three load currents.
MCP1642B-50
2014 Microchip Technology Inc. DS20005253A-page 21
MCP1642B/D
7.0 PACKAGING INFORMATION
7.1 Package Marking Information
8-Lead DFN (2x3x0.9 mm) Example
Part Number Code
MCP1642B-18I/MC AJY
MCP1642BT-18I/MC AJY
MCP1642B-30I/MC AJU
MCP1642BT-30I/MC AJU
MCP1642B-33I/MC AJQ
MCP1642BT-33I/MC AJQ
MCP1642B-50I/MC AJL
MCP1642BT-50I/MC AJL
MCP1642B-ADJI/MC AKC
MCP1642BT-ADJI/MC AKC
MCP1642D-18I/MC AKA
MCP1642DT-18I/MC AKA
MCP1642D-30I/MC AJW
MCP1642DT-30I/MC AJW
MCP1642D-33I/MC AJS
MCP1642DT-33I/MC AJS
MCP1642D-50I/MC AJN
MCP1642DT-50I/MC AJN
MCP1642D-ADJI/MC AKE
MCP1642DT-ADJI/MC AKE
AJY
348
25
Legend: XX...X Customer-specific information
Y Year code (last digit of calendar year)
YY Year code (last 2 digits of calendar year)
WW Week code (week of January 1 is week ‘01’)
NNN Alphanu meric tracea bil ity code
Pb-free JEDEC® designator for Matte Tin (Sn)
*This package is Pb-free. The Pb-free JEDEC designator ( )
can be found on the outer packaging for this package.
Note: In the even t the fu ll Microc hip p art numb er cann ot be mark ed on one line, it w ill
be carried over to the next line, thus limiting the number of available
characters for customer-specific information.
3
e
3
e
8-Le ad MSOP (3x3 mm) Examp le
42B50I
348256
MCP1642B/D
DS20005253A-page 22 2014 Microchip Technology Inc.
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BOTTOM VIEW
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2014 Microchip Technology Inc. DS20005253A-page 23
MCP1642B/D
Note: For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
MCP1642B/D
DS20005253A-page 24 2014 Microchip Technology Inc.
Note: For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
2014 Microchip Technology Inc. DS20005253A-page 25
MCP1642B/D
Note: For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
MCP1642B/D
DS20005253A-page 26 2014 Microchip Technology Inc.
Note: For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
2014 Microchip Technology Inc. DS20005253A-page 27
MCP1642B/D
APPENDIX A: REVISION HISTORY
Revision A (December 2014)
• Original Release of this Document.
MCP1642B/D
DS20005253A-page 28 2014 Microchip Technology Inc.
NOTES:
2014 Microchip Technology Inc. DS20005253A-page 29
MCP1642B/D
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, contact your local Microchip representative or sales office.
Examples:
a) MCP1642B-18I/MC: Industrial temperature,
8LD 2x3 DFN package
b) MCP1642BT-18I/MC: Tape and Reel,
Industrial temperature,
8LD 2x3 DFN package
c) MCP1642B-ADJI/MC: Industrial temperature,
8LD 2x3 DFN package
d) MCP1642BT-ADJI/ MC: Tape and Reel,
Industrial temperature,
8LD 2x3 DFN packa ge
e) MCP1642B-18I/MS: Industrial temperature,
8LD M SOP pac k ag e
f) MCP1642BT-18I/MS: Tape and Reel,
Industrial temperature,
8LD M SOP pack a ge
g) MCP1642B-ADJI/MS: Industrial temperature,
8LD M SOP pack a ge
h) MCP1642BT-ADJI/ MS: Tape and Reel,
Indus trial temperature,
8LD M SOP pac kage
a) MCP1642D-18I/MC: Industrial temperature,
8LD 2x3 DFN package
b) MCP1642DT-18I/MC: Tape and Reel,
Industrial temperature,
8LD 2x3 DFN package
c) MCP1642D-ADJI/MC: Industrial temperature,
8LD 2x3 DFN package
d) MCP1642DT-ADJI/MC: Tape and Reel,
Industrial temperature,
8LD 2x3 DFN packa ge
e) MCP1642D-18I/MS: Industrial temperature,
8LD M SOP pac k ag e
f) MCP1642DT-18I/MS: Tape and Reel,
Industrial temperature,
8LD M SOP pack a ge
g) MCP1642D-ADJI/MS: Industrial temperature,
8LD M SOP pack a ge
h) MCP1642DT-ADJI/MS: Tape and Reel,
Indus trial temperature,
8LD 2x3 MSOP pac kage
PART NO. X/XX
PackageTemperature
Range
Device
Device: MCP1642B: 1A, 1 MHz Low Voltage Start-up Synchronous
Boost Regulator With True Disconnect Output
MCP1642D: 1A, 1 MHz Low Voltage Start-up Synchronous
Boost Regulator With Input to Output Bypass
Outpu t Vo ltage: 18 = 1.8V
30 = 3.0V
33 = 3.3V
50 = 5.0V
ADJ = Adjustable Output Voltage
Temperature
Range: I= -40C to +85C (Industrial)
Package: MC = Plastic Dual Flat, No Lead – 2x3x0.9 mm Body
(DFN)
MS = Plastic Micro Small Outline (MSOP)
[X](1)
Tape
and Reel
Note 1: Tape and Reel identifier only appears in the
catalog part number description. This
identifier is used for ordering purposes and
is not printed on the device package. Check
with your Microchip Sales Office for package
availability with the Tape and Reel option.
X
Output
Voltage
MCP1642B/D
DS20005253A-page 30 2014 Microchip Technology Inc.
NOTES:
2014 Microchip Technology Inc. DS20005253A-page 31
Information contained in this publication regarding device
applications a nd the lik e is p ro vided on ly for yo ur con ve nien ce
and may be supers eded by updates . I t is you r r es ponsibil it y to
ensure that your application meets with your specifications.
MICROCHIP MAKES NO REPRESENTATIONS OR
WARRANTIES OF ANY KIND WHETHER EXPRESS OR
IMPLIED, WRITTEN OR ORAL, STATUTORY OR
OTHERWISE, RELATED TO THE INFORMATION,
INCLUDING BUT NOT LIMITED TO ITS CONDITION,
QUALITY, PERFORMANCE, MERCHANTABILITY OR
FITNESS FOR PURPOSE. Microchip disclaims all liability
arising from this information and its use. Use of Microchip
devices in life support and/or safety applications is entirely at
the buyer’s risk, and the buyer agrees to defend, indemnify and
hold harmless Microchip from any and all damages, claims,
suits, or expenses resulting from such use. No licenses are
conveyed, implicitly or otherwise, under any Microchip
intellectual property rights.
Trademarks
The Microchip name and logo, the Microchip logo, dsPIC,
FlashFlex, flexPWR, JukeBlox, KEELOQ, KEELOQ logo, Kleer ,
LANCheck, MediaLB, MOST, MOST logo, MPLAB,
OptoL yzer , PIC, PICSTART, PIC32 logo, RightTouch, S pyNIC,
SST, SST Logo, SuperFlash and UNI/O are registered
trademarks of Microchip Technology Incorporat ed in the
U.S.A. and other countries.
The Embedded Control Solutions Company and mTouch are
registered trademarks of Microchip Technology Incorporated
in the U.S.A.
Analog-for-the-Digital Age, BodyCom, chipKIT, chipKIT logo,
CodeGuard, dsPICDEM, dsP ICDEM. net, ECA N, In-Circuit
Serial Programming, ICSP, Inter-Chip Connectivity, KleerNet,
KleerNet logo, MiWi, MPAS M, MPF, MPLAB Cert ified logo,
MPLIB, MPLINK, MultiTRAK, NetDetach, Omniscient Code
Generation, PICDEM, PICDEM.net, PICkit, PICtail,
RightTouch logo, REAL ICE, SQI, Serial Quad I/O, Total
Endurance, TSHARC, USBCheck, VariSense, ViewSpan,
WiperLock, Wireless DNA, and ZENA are trademarks of
Microchip Technology Incorporat ed in the U.S.A. and other
countries.
SQTP is a service mark of Microchip T echnology Incorporated
in the U.S.A.
Silicon Storage Technology is a registered trademark of
Microchip Technology Inc. in other countries.
GestIC is a registered trademarks of Microchip Technology
Germany II GmbH & Co. KG, a subsidiary of Micr o chip
Technology Inc., in other countries.
All other trademarks mentioned herein are property of their
respective companies.
© 2014, Microchip Technology Incorporated, Printed in the
U.S.A., All Rights Reserved.
ISBN: 978-1-63276-905-3
Note the following details of the code protection feature on Microchip devices:
• M icrochip products meet the specification contained in their particular Microchip Data Sheet.
• M icrochip believes that its family of products is one of the most secure famili es of its kind on the market today, when used in the
intended manner and under normal conditions.
• There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
• M icrochip is willing to work with the customer who is concerned about the integrity of their code.
• Neit her Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
mean that we are guaranteeing the product as “unbreakable.”
Code protection is c onstantly evolving. We a t Microc hip are co m mitted to continuously improving the code prot ect ion featur es of our
products. Attempts to break Microchip’ s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Microchip received ISO/TS-16949:2009 certification for its worldwide
headquarters, design and wafer fabrication facilities in Chandler and
Tempe, Arizona; Gresham, Oregon and design centers in California
and India. The Company’s quality system processes and procedures
are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hoppi ng
devices, Serial EEPROMs, microperiph erals, nonvolatile memory and
analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
QUALITY MANAGEMENT S
YSTEM
CERTIFIED BY DNV
== ISO/TS 16949 ==
DS20005253A-page 32 2014 Microchip Technology Inc.
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03/25/14